The present invention is related to the field of integrated circuit testing.
As feature sizes have continued to decrease in the progression of integrated circuit technology, the challenges of adequately testing manufactured devices have grown. It has already become infeasible to include electrical test points at internal circuit nodes, and thus more recent testing approaches include optical techniques in which optical energy is focused at test locations. However, fundamental optical resolution limits have been reached even for current devices, and thus existing optical techniques is inadequate for accurate device testing in current and future semiconductor manufacturing processes.